Shovel-crane boom



L. A. RUSSELL SHOVEL CRANE BOOM March 20, 1928.

Filed July 2. 1924 I amounted, lflfimmcll GH -anew Patented Mar. 20,1928.

UNITED STATES 1,662,902 PATENT OFFICE.

LESLIE A. BUSSELL,- OF MILWAUKEE, WISCONSIN, ASSIGNOR TO KOEHRINGCOMPANY,

OF MILWAUKEE, WISCONSIN, A CORPORATION,

SHOVEL-CRANE BOOM.

Application filed July 2,

This invention has relation to excavating machines of the type knowncommonly as shovel cranes or power shovels, wherein 1s employed a shovelboom and dipper means 8 mounted on said boom, andoperated from the.

power plant carried by the body of the crane.

The ordinary operation of cranes of the above type contemplates anexcavating move ment of the dipper or shovel member usul ally involvingelevating action thereof as 1t is crowded to its work, a lateralswinging or sweeping of the dipper and its handle bywhich isconnectedwith'the boom, to bring the dipper into an unloading positionover a vehicle or a place on which the contents .of the dipper may bedumped, and a subsequent restoration of the dipper by reverse operationsto bring it back to its excavating position. Now it is well known in theart that with the usual types of supporting boom, dipper and dipperstick or handle constructions a rigid mounting of the boom upon thecrane is usually provided. The dipper stick either straddles thesupporting boom therefor, or passesbetween spaced parts of such boom inthe usual constructions. The sad stick forms a long lever, and theoperat ons of the crane usually are such that as the .car

or body of the crane turns to swing the boom and the dipperinstrumentalities considerable momentum of these arts is created intheir movement. The or 'nary operation of the machine furthermore, forefilciency, requlres rather sudden stop age of the boom IDOVB'.

ment in swin in t is being true both when the dipper is oa ed and whenit is unloaded.

, Necessarily this action of the boom and dipper in the stoppingmovements creates severe stresses and strains both upon the l 40 boomsupporting means at the point of connection w1th the crane body or carand upon the dipper stick or handleitself. At times the operator ofthemachine accidentally sideswipes a vehicle or bank or other obstacle,giving rise to additional severe stream on the connections at the footof the boom and the di per stick of the dipper.

Ihe object of the present invention has been to produce, a comparativelysimple dipper su porting boom construction, wherein the b0 y of the boomis mounted, practically speaking, for turning movement relatively-to thefoot of the boom, about an axis longitudinally of the boom, the saidbody andfoot members of the boom being maintamed in 1924. Serial No.723,623.

their normal positions by resilient means such as springs. These springsare designed to absorb the shocks and stresses to which the boom anddipper stick may be subjected inci dent to their use in ordinaryexcavating oper-' ations.

The foregoing resilient mounting of the boom, or its facility toturnabout a longitudinal axis, is advantageous for general mechanicaloperations, previously discussed, and is additionally advantageous froma.- manufacturing view-point because the construction of the supportingmeans for the boom'is not required to be so heavy and shock resistant asotherwise is the case, and furthermore this same thing applies to theconstruction of the dipper stick or handle as well.

In the accompanying drawings,

Figure 1 is adiagrammatic side view showing a shovel crane equipped withthe constructional features embodying my invention.

Figure. 2 is a longitudinal sectional view of a somewhat fragmentarynatureshowing absorbing shocks'incident to lateral stresses transmittedto the boom through the dipper means thereof. a v

Figure 3 is a side view showing substantially the same parts as areillustrated in Figure 2. 1

Describing my invention; specifically, I. designate the car or body ofmy crane at A in Figure 1, and the traction sup ort thereof at B, thelatter being composed traction members, and there being provided theusual swing body or turntable mounting intermediate the car A and saidtraction support B. My shovel boom or boom element is designated at 1and is supported by the foot 2. The dip 'er is desi ated at 3 and isconnected to an supporte by the boom by the dipper stick 4. The dipperis hoisted by the hoisting cable 5, and suitable crowding out andracking in mechanism may be emof endless,

ployed of a more or less conventional nature so far as the inventionhereof is concerned.

It will be observed that the dipper stick 4.

straddles the boom l-according to my particular constructionillustrated, although this is not a necessary feature of the said COD:

struction because my iinvention is adapted to upon any suitable bracketmeans projecting from the car A of the crane. lhe outer portion of the.boom foot 2 is equipped with a longitudinal bearing, opening 7 in whichis journaled the round journal end portion 8 of a boom casting 8, theopposite end of which is of square form and fits into the lower end ofthe body of the booml. Rivets or other suitable fastenings 9 may beemployed to rigidly connect the boom casting 8, which is virtually ajournal casting be--- cause it provides the journal member 8, withrespect to the boom 1. At opposite sides of the boom 1 and .at its lowerend adjacent to the square extremity. of the casting 8, are attachedplates 10 b like, and these pl a downwardly off-standing arms or lugs11. The lugs 11 are provided with apertures through which pass bolts orrods 12, which bolts also pass through spring casings or housings 13that are preferably cast with the foot member 2 of the boom. The casings13 enclose a. spring or springs of the expanding coil type designated at14, and mounted in each casing 13 at its upper end is a plate 15 havinga sleeve extension 16 that passes through the upper end of the casingand abuts with the under-side of the adjacent In 11. At its lower endthe casing has a secon plate 17 which abuts with the lower ends of thesprings, and is under-hung by an. abutment portion 2 on the foot member2. 'A nut 18 is screwed upon the upper end of each bolt 12, and the head19 of each bolt has an abutment relation with the under-side of thead'acent plate 17.

n eflect, therefore, the boom 1 has radial projections 11, and the footmember 2 0 posed radial projections 13 with interme iately actingresilient devices.

It is to be noted that the casingsysprin and lugs or arms above setforth are norma y disposed in substantially vertical planes in opppsitesides of the boom 1 and its foot memr 2. Furthermore, normally thesprings 14 by their expanding action hold the parts 15 and 17 at theopposite ends of the casin 13. But said springs when compressed a lowfully rotary play of the booml in the foot member 2 b reason of theprovision of the journal mem er 8'. In view of the foregoing features ofconstruction it will be obvio'us that many shocks or stressestransmitted to the boom 1 andtcndin to twist the boom by torsionalaction, whic stresses and shocks are common todayin shovel cranes, willbe absorbed by a yielding turning movemeans of rivets or the tes areequipped with,

ment of'the boom 1.on its member 2.

In other words, the boom 1 is capable of rotating relatively to the foot2 and the said shocks or stresses are fully absorbed by the provision ofthe springs 14. It is notable,

too, that the springs 14 at opposite sides of vice-versa, whereby thesprings at both sides" of the boom are'utilized in lending their resistance to compression incident to-the absorption of the stressesinvolved in the rotative taming tendencies of the boom as transmittedthereto by the dipper stick in the constant swinging and stoppingmovements of the latter. 7

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is,

1. Ina crane of the class described, in

combination, a swing body, dipper shovel mechanism comprising a boomelement, a dipper shovel mounted thereon, and a connection between theswing body and the said boom element comprising shock absorbing meansmaintaining the boom element in a certain normal relative position tothe swing body but adapted to yield upon undue resistance to themovement of theshovel as 'it is swung with the swing body.

2. In a crane of the class described, in combination, a swing body, ashovel supporting boom element, a dipper shovel mounted thereon, meansfor racking in and crowding out the said dipper shovel, and an operativeconnection between the said boom element and the swing body comprisingshock absorbing springs normally acting to hold the boom element in acertain position with its dipper shovel, in relation to the swing body,the said shock absorbing springs being adapted to yield and", 'ermit ofrelative movement of the boom e ement laterally in respect to the swingbody when the dipper shovel meets with undue resistance as it is swunglaterally with the boom element in working operations.

3. In a crane construction of the class described, in combination withthe body of the crane, aboom construction includin a foot memberconnected with the body a oresaid, anda boom body member rotative abouta upon the foot member, together with yielding means intermediate theboom body and foot members whereby to resiliently maintain them innormal operative sitions.

4. In a crane of the class escribed,

combination, a. crane body, a boom mounted I thereon, shovel meanscomprislng a' dipper and dipper stick connected to the boom, the saidboom embodying resiliently connected longitudinal axis relatively to andmounted I mitted by the swing body.

- movements of the members ada ted for movement relatively to each othera out an axis longitudinally of the boom.

5. In a crane of the class described, in combination, a swing body, ashovel supporting boom element, a dipper shovel mounted upon said boomelement, mechanism on the swing body for racking in and crowding outthedipper shovel as it is carried by the boom element, and a mountingconnection intermediate the boom element and the swing body andcomprising cushion devices to absorb the shock incident to abnormalresistance to the lateral swing of the boom element when the dippershovel meets with resistance the said cushion devices acting to absorbshocks set up by the undue stresses transthe shovel to the boom elementand therefrom to the said connection with 6. As a new article ofmanufacture, a power shovel boom comprising a foot memher, -a' bodymember movably mounted upon the foot member, and resilient meansintermediate the two for absorbing the shocks or stresses reated bysweeping and stopping boom under actual conditions of service. 4

7. A boom unit structure for shovel cranes comprising a foot member, abody member movably connected to the foot memher, and yielding devicesintermediate the two comprising springs mounted upon one of said parts,lugs carried by the other of said parts cooperative with said springs,and connections between the lugs and springs substantially as described.

8. In combination a crane body, shovel boom apparatus carried therebyincluding a boom, a dipper stick and dipper carried by 'said dipperstick, the boom comprising a foot memberconnected with the crane and abody member and carrying the dipper stick movably mounted upon the footmember, together with resilientmeans intermediate the boom foot memberand the boom body memher for absorbing shocks as an incident t relativemovement of said parts.

9. A boom structure for power shovels comprising, a foot member, a bodymember rotatively mounted upon the foot member and resilient connectingmeans between the body member and the foot member located at oppositesides thereof, said resilient means including springs so connected withthe foot and body members that. the sp'ring'means at one side of theboomcooperates to resist transmitted 'to the boom element,.

twisting or turning of the body of the boom in either direction.

10. A boom structure for power shovels comprising a foot member havingspring casings'at opposite sides thereof, a body member havingoff-standing arms at opposite sides thereof terminating in line with thesaid casings, journalin'g means between the foot and body membersincluding a journal casting having a square end portion fastened to thebody member and the round journal end portion fitting into and rotatableon the foot member, together with springs and spring connecting partscarried by the casings and attached to the said arms of the foot memberand body member substantially as set forth and described.

11. A revolving crane body, a boom assembly comprising a rockable boomfoot pivoted to the said body for swinging in a verti-v cal plane and aboom arm longitudinally journalled in the boom foot, a dipper sticksupported by the said arm, resilient means normally maintaining'the saidstick and the said arm in planes, parallel with the crane bodys verticalcenter line while allowing the said arm and the dipper stick aforesaidto depart therefrom under stress in either lateral direction,

12. A shovel boom comprising a vertically rockable boom foot and arotatable boom arm, resilient means oppositely positioned adjacent thesaid foot and said arm, op-

posed shoulder formationsupon the rockable boom foot and upon therotatable boom arm to offer abutting 13. A shovel boom comprising twoelements, at non-rotative foot member and a rotative arm, opposed radialprojections outstanding from the said member and the said arm, resilientmeans aifecting the said projections to resist rotation of the saidarm,

flanges limiting a longitudinal bearing connecting the said foot and thearm aforesaid.

the said means located for responding to LESLIE A. RUSSELL;

